Step |
Hyp |
Ref |
Expression |
1 |
|
climrel |
|- Rel ~~> |
2 |
|
climuni |
|- ( ( x ~~> y /\ x ~~> z ) -> y = z ) |
3 |
2
|
ax-gen |
|- A. z ( ( x ~~> y /\ x ~~> z ) -> y = z ) |
4 |
3
|
ax-gen |
|- A. y A. z ( ( x ~~> y /\ x ~~> z ) -> y = z ) |
5 |
4
|
ax-gen |
|- A. x A. y A. z ( ( x ~~> y /\ x ~~> z ) -> y = z ) |
6 |
|
dffun2 |
|- ( Fun ~~> <-> ( Rel ~~> /\ A. x A. y A. z ( ( x ~~> y /\ x ~~> z ) -> y = z ) ) ) |
7 |
1 5 6
|
mpbir2an |
|- Fun ~~> |
8 |
|
funfn |
|- ( Fun ~~> <-> ~~> Fn dom ~~> ) |
9 |
7 8
|
mpbi |
|- ~~> Fn dom ~~> |
10 |
|
vex |
|- y e. _V |
11 |
10
|
elrn |
|- ( y e. ran ~~> <-> E. x x ~~> y ) |
12 |
|
climcl |
|- ( x ~~> y -> y e. CC ) |
13 |
12
|
exlimiv |
|- ( E. x x ~~> y -> y e. CC ) |
14 |
11 13
|
sylbi |
|- ( y e. ran ~~> -> y e. CC ) |
15 |
14
|
ssriv |
|- ran ~~> C_ CC |
16 |
|
df-f |
|- ( ~~> : dom ~~> --> CC <-> ( ~~> Fn dom ~~> /\ ran ~~> C_ CC ) ) |
17 |
9 15 16
|
mpbir2an |
|- ~~> : dom ~~> --> CC |